Could our white butterflies soon be facing extinction?

Three of the best known species of these white beauties could be extinct in Britain by 2050 unless efforts are made to manage landscapes better so they can survive the impacts of drier

conditions.  The three white butterflies – the large white, small white and green-veined white – are three of six species that conservationists fear could vanish.  Experts led by Dr Tom

Oliver from the UK’s Centre for Ecology and Hydrology focused on butterflies when they began to look at the impacts different carbon dioxide emission rates would have on wildlife. 

Butterflies were chosen because they are among the best studied species and there is lots of information about their year-to-year abundance. The team looked at data for 28 species of

butterfly from 129 sites alongside historic climate records and habitation information from the UK Land Cover Map.  Their findings – published today in the scientific journal Nature Climate

Change - might please cabbage growers whose crops are readily eaten by the whites’ caterpillars, but the loss of some of our most eye-catching and regularly seen butterflies would make

summer in Britain all the less enjoyable. White butterflies have recently come under the spotlight from energy experts who believe their wing shapes hold the answer to more efficient solar

farms.  Fears that white butterflies may vanish were raised when Dr Oliver’s team, which also included scientists from Butterfly Conservation, Natural England and the University of Exeter,

discovered six species as having a “low probability of persistence” by 2050 even under the most favourable emissions scenarios.  Besides the three species of white butterfly, there ae also

concerns for the ringlet, speckled wood and large skipper.  Dr Oliver said: “The results are worrying. Until I started this research, I hadn’t quite realised the magnitude and potential

impacts from climate change. For drought-sensitive butterflies, and potentially other taxa, widespread population extinctions are expected by 2050. To limit these loses, both habitat

restoration and reducing CO2 emissions have a role.. In fact, a combination of both is necessary.  “We consider the average response across Great Britain. Losses are likely to be more severe

in drier areas with more intensive land use, while wetter areas with less fragmented habitat will provide refugia.  “We assume that butterflies won’t have time to evolve to become more

drought-tolerant, because their populations are already small, and evolution would need to be very rapid. “The study looked at butterflies but the conclusions are potentially valid for other

species such as birds, beetles, moths and dragonflies.”  Experts who took part in the study say it shows the “pressing need” to investigate local conservation measures to help

drought-sensitive butterflies to adapt as well warnings that the insects are only likely to avoid widespread extinctions if carbon dioxide emissions are reduced below business-as-usual

levels.  Co-author Mike Morecroft from Natural England said, “There’s good news and bad news here. The good news is that we can increase the resilience of species to climate change by

improving our natural environment, particularly increasing areas of habitat and we are working hard at this. However, this approach will only work if climate change is limited by effective

controls on greenhouse gas emissions.”